How to replace deleted vertices?
As far as I understand your problem:

Select vertices 1 and 2. Press J to join them. This will create an edge, cutting through an existing face. Now you can right-click, subdivide and choose 3 as the number of new vertices (marked as 3, 4 and 5 above):

From here you could connect horizontal pairs 3 &amp; 6, 4 &amp; 7, 5 &amp; 8, also by selecting a pair and pressing J. Then, finally, you can select vertices 9 &amp; 10, press J to do a cut there as well to get quads. But then you need to press ⌘ + R for a loop cut to divide the quads above vertex 9 and below vertex 10. You would have to do the same right to 6 and 8.
Of course everything would be simpler if you just selected vertex 8, pressed G twice and moved it to the nearest vertex, similarly with vertices 6, 9 and 10, then if vertex auto-merging is disabled, you would press A then M then B to select all vertices and remove doubles, but I assumed those vertices are there for a reason.